Variable speed transmission mechanism



Aug. 7, 1945. c. D. BUCK v I VARIABLE SPEED Tmmsms slcm MECHANISM Filed June-22, 1942 4 Sheets-Sheet 1- v WMINVENTiOR. w i

- Aug. 7, 1945. c. D. BUCK v 2,381,805

VARIABLE SPEED TRANSMISSION MECHANISM Filed Jun e 22, 1942 a 4 Sheets- Sheet 2 V Y T il:

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1 35 r I: gr: 54 7 i; 3 13? x "annual!" g INVENTIOIR.

Aug. 7, 1945. c. D. BUCK VARIABLE SPEED TRANSMISSION MECHANISM 4 Sheets-Sheet 5 Filed June 22, 1942 7, 1945. 7 c. D. BUCK. 81,805

VARIABLE SPEED TRANSMISSION MECHANISM.

Filed June .22, 194; v 4 shee ts sh'eet 4- I /9 032f Ag 6 1 22 ,LQMINVENMR.

' Patented Aug. L 1945 vAm nLE SPEED TRANSMISSION MECHANISM .Clyde D. Buck, Fremonalnd. 1

1942, serialivmnwos 4 Claims. (01. 192 -35) Application June 22,

' This invention relates tomechanism for automatically shifting' 'gears, adapted for example to thevariablesp'eed transmission mechanism for automobiles andother apparatus.

An object of the invention isto power transmission mechanism having gears arranged so that by Shifting of certain of the gears into amrem engaging positions with other gears, the speed ratio between "a drive shaft and. a propeller shaftfisselectively varied, an automatic means ior shifting the gears from one engaging position toanother'according to the speed of the propeller shaft, particularly from low speed to intermediate speed 'anclfrom intermediate 'speedfto high speed in successive order, and vice VersaJ V Another object of the invention isto provide in a power transmission mechanism having speed change gears, a propellershaft, and alined drive shaft actuated by'a motor'driven clutch, a mechanisrn for automatically,shifting the gears from 'one positonto anotlieraccordingto the speed of the propeller shaft,- and another mechanism oneratively associated with the shifting gears by whichflto movethe clutch-out 'of action durin movement'of theshift'gears from one engagin posltontoariothei T And. 9. 'further 'object' of the: invention is to provide in a power transmitting'mechanism having speed" han'ge gearing associated with a propellershaftand a clutch operated drive shaft, a manually operated means for throwing the clutch out 'of action, and another mechanism operatively associated "with said: gearing for automatically I movingth'e clutch 'out of "action during'movement of thejshift gears from one engaging position-to another independently of saidfmanually op'erated clutch controlling means; l 1

".1 Other objects andadv'an ta'ge's of theinvention appear ini'th'e following description. 1

' illustrative embodimentof the invention is shown irr'the accompanying drawings, in which: :Fig; lis' -a side'elevational view of a speed change transmissionmechanism in which the invention-is incorporated; the view being shown in'section; i

Fig; 2 is a detail view showing the abutting end portions'of a propeller-"and drive shafts'used in the transmission mechanism, the drive shaft being partially in section; p 1 w '--Fig. 3 is a detail view showing part-of the gear shifting 'mechanism, partially cut away and in section on the line'3-3 of Fig, 1; L

' Fig. 4' is "a view showing a vertical transverse section of Fi'g; 1 'o'n- -the line 44 thereof; 1

provide in a Fig. 5 is a detail view of 'a part projected from Fig. 4 in a plane at right angles thereto; i

Fig. 6 is-a detail top planv iew of part of the structure shown in Fig. 4;

Fig. '7 is a fragmentary side elevational view of a car body equipped with manually operated means for ,control of certain gears in the transmission mechanism; I h i i Fig. .8 is a detail view of jmechanisrn shown in Fig. '7, in section on the line 8-8 -thereof, and drawn to an increased scale;

Fig. '9 is an endelevational view of the governor mechanism for controlling the shift gears, the propeller shaft being shown in section;' f

Fig. 10 is a detail top plan View, of the gear shifting mechanism;

Fig-11isa detailplaniview of a pair of the governor arms;

Fig. 12 is a detail transverse cross sectional view of reverse gearing, the section being on the line l2--l2 ofFi'g.,l; i M

Fig.- 13 is a fragmentary side elevational View .of the. governor-rand shift gearing disposed in first speed or low gear position; and

r Fig. 14 is another similar fragmentary view showing the gearing in second speed or intermediategear position. a I

The invention as illustrated consists of. a speed change power transmitting mechanism actuated by a motor driven clutch through the medium of whichv rotary movement is imparted in various ratios to a propeller shaft.

The clutch preferably is ofthe usual type having a drag plate lsplined on atransmission shaft 2, axially alinedwithadrive shaft3, of a motor I (not shown), and friction discs 4 disposed between the drag plate and the fly wheelfinfor the motor. ;-In this instance=there isprovided a sleeve 6, ,loosely mounted on the transmission shaft 2, and levers I pivoted in the flywheel structure, having'engagement with said sleeve and drag-plate, through the medium of 'which the clutch is thrown into and out of action upon axial movement of the sleeve. i

The speed changemechanism has .a gear case 8 in which are mounted, in axial alinement,-said transmission shaft :2 and a propeller shaft 9, there being a stud H] on one of said shafts that extends loosely into-the other shaft by which alinement. of said shafts is maintained The transmission shaft-2 has a similar stud II that extends loosely into the motordrive shaft 5" for the same purpose. By this arrangement the motor shaft,ntransmission shaft and the propeller and 9.

v of both the transmission shaft and the propeller shaft where the sleeve has splined engagement with both of said shafts, thus to establish'direct driving relation therebetween.

The rear end of the shift-sleeve l3'has thereon an annular flange 16 that isrengagedby a loose ,extends into the path of the lever member 28 so that when the rock-lever '36. is depressed by action of shaft accordingly is turned through the medium of said jaws causing movement of the clutch sleeve 6 forwardly through the medium of the lever member 28, thus throwing the clutch out of action.

In the housing 21 is mounted an oscillating shaft 34 having thereon a member provided with an annular series of cams 35 which has operative engagement with a rock lever 36 that is pivotally mounted ,upon a stud 31 projecting from a boss 38 in the housing. An arm 36' on the rock lever the pendant lug 39 on any one of the cams 35 the clutch sleeve 6 is moved forward through the medium of the lever member 28, independently with respect to action of the pedal 3|.

concentric collar I1, and the propeller shaft 9 has keyed thereon a gear l8 located at a point spaced fromthe abutting ends'of the shafts 2 Upon the propeller-shaft is disposed a spider consisting of a rim l9, hub 20, and radial spokes 2|,the hub being splined on the shaftig so as to have relative axial movement thereon. Uponeach spoke is loosely disposed a governor weight 22 and a corresponding compression spring 23, said spring being locatedbetween the rim and the weightand has the tendency to restrain radial outward movement. ;thereof. Mounted concentrically, with the axis of the shaftsv 2 and 8 is a contraction spring 24 the ends of which are secured respectively to. the hub. l8 of the gear I8 and. the collar {1, which has the tendency to urge the collar and the shift gears rearwardly toward the gear. Ill.v Each weight22 has pivoted thereon a pair of governor arms 25 that have also pivotal connection with the hub of the gear l8 and the collar -I! respectively. Preferably, one of each pair of arms extend astride the corresponding weight and the other pair of arms, thus to afford extended radii of action thereof. When the spider is revolved, upon rotation of the propeller shaft 5, the governor weights 22 tend to slide radially outward upon the spokes in oppositionto resistance of the spring 23 because of centrifugal force, aided by a contractive force of thespring 24. As the weights move outwardly, the spider and the collar IT with its associated'step, gears move axially toward the gear 18, said movement being occasioned through the medium of the governor arms. In this manner" the shift gears are adjustablymoved axially to an extent correspondingly asthe speed of the propeller shaft varies.

Rearward movement of the shiftgearmember is aided by the contractive 'l l'ge. of the spring 24 in opposition to resistance of the springs 23. The urge of the'sprin'g 24 and restraint of the springs 23 are such that when the propeller shaft is motionless the weights are balanced in their innermost positions and the shift gear member is then disposed'in 'its' forwardmost position.

A rock-shaft 26 is mounted in the 'fly wheel housing 27 andhas secured thereon a lever member 28 that is connected by'means of pivots 29 with the clutch sleeve 6, so that axial movement of the sleeve is occasioned upon rocking of the shaft 26. The outer end of the rock shaft 26 has loosely mounted thereon an actuating lever 30 that has linked connection with a pedal 3|, and is provided with a lateral jaw 32 that overlaps another jaw 33 which is secured'on the outer end of the rock shaft. Upon manual operation of the pedal 3! inone direction the rock A longitudinally movable shaft 40 is suitably mounted in the forward part of the gear case and has mounted on its inner end a fork 4| the arms of which extend-astridethe shift sleeve, l3 in an annular-groove '42 made therein, so that upon axial movement of the shift gears corresponding movement thereby is imparted to the sliding shaft 40. The oscillating shaft 34'hassecuredthereon a pinion 43 that has toothed engagement with a rack 44 secured on the slide shaft 40, so that axial movement of the shift gear member is accompanied by rotary movement .of the oscillating shaft and the series of cams thereon, thus causing the clutch. to be thrown out of or let into action through the medium of the-rock lever 36.

In the gear case 8 is mounted a countershaft 45 having fixed thereon step gears 4'6'and 41 that have operative engagement selectively with the shift gears l3--l4 accordingly as the shift gears are adiustably positi0ned.wThe countershaft 45 has splines '48Hmade therein and has mounted thereon an axially slidable sleeve engaged with said splines. Said slidable sleeve has secured thereon-a gear engageable in; one position with the propellershaft gear [8 accordingly as adjusted. Upon said sleeve 49 is secured another gear 51 that has toothed relation'with an intermediate gear 52 -which is supported upon an adjustably movable frame 53 in th gear case. The countershaft 45 and the gears 50 and 5f rotate together, and-are axially movable with respect=to the countershaft together with themovable frame 53, so that upon adjustment of. the sleeve 49-the gear 50 and the intermediate gear 52 are selectively moved into and out. of-engagement with the propeller shaft gear Hi. This operation is to effect reverse movement of the propeller shaft accordingly as said frame is shifted from one position to-another. I An adjustingmember consisting of a fork 55- is disposed astride of the sleeve 49 in the groove 56 made therein, and has a contiguous rack bar 5'l-mounted in'a guide 58 in the gear case by which axial adjustable movement is imparted .to said sleeve. The rack barhas engagement with a pinion 59 secured upon an operating shaft 60 that is manually oscillated through the medium of suitable mechanism, such as shown in Figs. '7- and '8, which is provided with a handle 6| conveniently located within the operators reach as in-th cab 62.- .The mechanism for actuating th shaft 60 is such as is. ordinarily employed for imparting adjusting movementto reverse gear mechanism, the structure shown being exemplar r In operation, the clutchis normally heldin active position bysprings (not shown) that press the drag plate in the usual manner against the friction. discs; so. that rotation of the'fly wheel causes the. transmissionishaft to revolve. By apment of the rock-lever sleeve 49 is selectively shift sleeve to move said mechanism into said low plying pressure upon the pedal the clutch is thrown out of action whereupon the transmission mechanism idles as in the usual practice.

As the propeller shaft 9 rotates, the governor mechanism including the gear l8, spider and the resistance due to the engaging step gears on the and countershafts and theengage- 3 6 with the cams 35, Whereupon potential force develops by centrifugal action of the governor weights which becomes effec tive when the foot pedal is depressed which releasespressure of the rock -lever against the cams 35. Thus, the shift sleeve I3 is automatically moved to the nextsucceeding position of adjusttransmission ment, such as from low-gear into intermediate gear, orfro-m intermediate gear into high gear position. In similar fashion the shift-sleeve I3 is automatically moved from high gear through intermediate, gear into low gear adjustment by reactionary force of the governor springs 23 as the speed of the propeller shaft 9 decreases upon manipulation of the foot pedal 3|.

Normally, the propeller shaft gear l8 and coup tershaft gear 50 have engagement with each other so movement is imported through the stepgears and countershaft to when either of the shift gears I4-! 5 are engaged, and when the shift sleeve I3 is in high gear position the countershaft idles.

By manipulating the handle 6! the adjusting moved forwardlyto disengage the drive gears' 50 and I8 whereupon the countershaft idles in neutral position, or upon further moving the verse gears 5 52 are brought into operative relation with the propeller shaft gear l8.

By the provision of the compression spring 23 and the contracting spring 24 in their operative relations with the governor weights and shift sleeve, the shift gears normally are disposed in low gear and are moved into intermediate gear or high gear only at times when the speed of the propeller shaft is suited to a particular change of the gear ratio. In this manner is circumvented shifting from the lower speed positions into the next higher speed position until the propeller shaft reaches a proper velocity.

Variations from the particular construction above disclosed may be resorted to by the exer cise of skill in the art without departure from the spirit or scope of the invention, and the following claims areintended to be inclusive of such variations.

What I claim is:

1. In speed change power transmitting mechanism having a motor-driven clutch, a transmission shaft and a propeller shaft alined upon a common axis, and provided with gearing disposed for adjustment selectively into low gear, intermediate gear, high gear, neutral and reverse gear positions, a lever control forsaid clutch, a gear sleeve 49 forwardly the regear, intermediategear and high gear positions, a centrifugal governor rotatable by said propeller shaft provided with a connecting collar operatively engaging said shift sleeve, a contraction spring attached to said collar to urge movement thereof toward high gear position, compression springs arranged to restrain the centrifugal action of said governor, and a mechanism engaged by said sleeve and the clutch control to prevent shifting of the sleeve while the clutch is in action,

2. In speed change power transmitting mechanism havin a motor-driven clutch, a transmisthe propeller shaft sion shaft, and a propeller shaft alined upon a common axis and provided with gearing disposed for adjustment selectively into low gear, intermediate gear, and high gear positions, a lever control for said clutch, a gear shift sleeve to move said mechanism into said low gear, intermediate gear and high gear positions, a centrifugal governor rotated by said propeller shaft provided with aconnecting collar operatively engaging said sleeve, a contraction spring attached to said collar to urge movement-thereof toward high gear position, compression springs arranged to restrain the centrifugal action of said governor, and a mechanism engaged by said sleeve and the clutch control to prevent shifting of the sleeve While the clutch is in action.

3. In power transmission mechanism where a transmission shaft and a propeller shaft axially alined therewith are mounted in conjunction with speed change gearing that includes a driven gear secured on the propeller shaft and a shift gear member splined on the abutting portions of said shafts, a governor consisting of a spider splined on said propeller shaft, radially movable weights supported by the spider, compression springs restraining centrifugal action of said weights, oppositely disposed groups of bifurcated arms connectedly related with the shift gear member and the propeller shaft extending astride the corresponding weights and pivoted to the far ends thereof, and acontracting spring the oppo,

site ends of which are connectedly related respectively to the shift gear member and the propeller shaft wherefore to urge axial movement of a said shift gear member in opposition to the restraint' of said compression springs.

4. In power transmission mechanism where a transmission shaft and a propeller shaft axially alined are mounted in conjunction with speed change gearing that includes a driven gear on the propeller shaft and a shift gear member splined on the abutting portions of said shafts, a centrifugal governor having a spider splined on the propeller shaft, radially movable weights supported by the spider provided with pivoted arms oppositely disposedthat have operative connected relation respectively with the shift gear member and said propeller shaft, compression springs to restrain centrifugal action of said weights, and a contraction spring connectedly related to said member and the propeller shaft wherefore to counterbalance restraint of said compression springs.

CLYDE D. BUCK. 

